DISASSEMBLY - TM-9-4910-736-14-P0079

TM 9-4910-736-14&P

3-4. REPAIR . Repair consists of replacing defective components. This is

accomplished by first disassembling the test set (paragraph 3-5) to the extent

required to gain access to the defective component, replacing it and then re-

assembling (paragraph 3-6) the test set. Once the defective component has

been replaced, perform the applicable adjustment (paragraph 3-7) and test

procedure (paragraph 3-8). Refer to the parts lists in Section V which contains

ordering information for replacement parts (part number, vendor. etc.).

3-5. DISASSEMBLY. Use the following procedures to disassemble only to the

extent required to gain access to the component to be replaced.

Remove 12 screws (MP129 through MP140, figure 5-4) and lift out front

panel and printed circuit board assembly. Access to the printed circuit

board components is now available.

To remove the printed circuit board assembly, remove four screws (MP72

through MP75, figure 5-2) and eight washers (MP76 through MP83) and

lift it off the four standoffs (MP30 through MP33, figure 5-l). Access

to the back of the front panel assembly is now available.

c. To remove a component from the front panel assembly see figures 5-1, FO-3,

and 5-4. Figures 5-1 and 5-4 are rear and front views of the front

panel assembly with reference designation callouts of the components and

their attaching parts. Figure FO-3 shows the electrical cables and

wiring between the front panel and the printed circuit board.

To remove a component from the printed circuit board assembly, see

figure 5-3 which shows wiring between printed circuit board and front

panel assembly. Also, see figure FO-2 which locates and calls out

components mounted on the printed circuit board assembly.

3-6.

REASSEMBLY. After the defective component has been replaced and rewired,

reassemble the test set. Then perform the applicable adjustment and test

procedure necessary to restore the equipment for use.

ADJUSTMENT PROCEDURES. The following procedures should be accomplished

3-7.

when it is found that the test set is out of adjustment or after a defective

component has been replaced. The following paragraphs contain equipment setup

procedures and procedures for adjusting the protection circuit, condenser leakage

test circuit, condenser series resistance test circuit, condenser capacitance

test circuit, ohmmeter test circuit, and coil test circuits. In addition,

procedures for securing trimmer potentiometers are given.

Equipment Setup.

Proceed as follows.

(1) Set FUNCTION switch to OFF position and remove 1.2 screws from

front panel so that access to the printed circuit card may be

gained. Check that meter indicates zero on the lower scale.

(2)

Connect the BAT LEADS (red + lead to + terminal and black - lead

to - terminal) to battery or power supply.

Set FUNCTION switch to OHM.

(3)

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